Robust Adaptive Control for Nonlinear Discrete-Time Systems by Using Multiple Models

<table class="table-group" width="800px"><tr class="fig-image" id="a"><td><img alt="679039.fig.003a" src="https://static.hindawi.com/articles/mpe/volume-2013/679039/figures/679039.fig.003a.jpg"/></td></tr><tr class="fig-caption"><td align="center"><table><tr><td><b>(a) </b>System output pH<svg height="15.1125" id="M209" style="vertical-align:-2.3205pt" version="1.1" viewbox="0 0 20.4375 15.1125" width="20.4375" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink">
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</svg></td></tr></table></td></tr><tr class="fig-image" id="b"><td><img alt="679039.fig.003b" src="https://static.hindawi.com/articles/mpe/volume-2013/679039/figures/679039.fig.003b.jpg"/></td></tr><tr class="fig-caption"><td align="center"><table><tr><td><b>(b) </b>Control input <svg height="15.1125" id="M210" style="vertical-align:-2.3205pt" version="1.1" viewbox="0 0 29.5875 15.1125" width="29.5875" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink">
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t114 146l32 145l74 26h11q-52 -199 -80 -347q-8 -39 6 -39q7 0 32 17.5t47 39.5z" id="x1D462"></path></g><g transform="matrix(.017,-0,0,-.017,9.208,12.162)"><path d="M300 -147l-18 -23q-106 71 -159 185.5t-53 254.5v1q0 139 53 252.5t159 186.5l18 -24q-74 -62 -115.5 -173.5t-41.5 -242.5q0 -130 41.5 -242.5t115.5 -174.5z" id="x28"></path></g><g transform="matrix(.017,-0,0,-.017,15.089,12.162)"><path d="M480 416q0 -21 -18 -41q-9 -11 -17 -7q-20 9 -42 9q-62 0 -140 -78q23 -69 88 -192q17 -31 27 -42t20 -11q16 0 62 46l17 -20q-64 -92 -119 -92q-35 0 -70 66q-41 73 -84 187q-36 -30 -62 -61q-27 -115 -35 -172q-41 -8 -78 -20l-6 6l140 612q7 28 0.5 34t-37.5 7l-34 1
l5 26q38 4 74 13.5t57 17t25 7.5q12 0 4 -32l-104 -443h2q35 38 97 93q39 35 65.5 56t62 41.5t58.5 20.5q19 0 30.5 -10t11.5 -22z" id="x1D458"></path></g><g transform="matrix(.017,-0,0,-.017,23.64,12.162)"><path d="M275 270q0 -296 -211 -440l-19 23q75 62 116.5 174t41.5 243t-42 243t-116 173l19 24q211 -144 211 -440z" id="x29"></path></g>
</svg></td></tr></table></td></tr></table>

<table>One adaptive mode with variable parameter.</table>

Mathematical Problems in Engineering

fig3

Figure 3

Figure 3: Robust Adaptive Control for Nonlinear Discrete-Time Systems by Using Multiple Models 